Oil-burner



B. S. ROTHWELL.

OIL BURNER.

APPLICATION FILED 0011. 1919.

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-' perspective of the inner portionofth'e mixer aperture acts as the outlet opening 01 .-:i noaj zle-for the burner.

1H1 ;Iran-"STATE :orrrc'r-ay 3113mm s; nom orcmvntmfon xo.

To all whom it may condemt: '1

Be it known that I, BERTRAM S. ROTH- wELL, a citizen of the United States, and a resident of Cleveland, county of Cuyaho'ga and State of'Ohio, have invented a new; and

-useful Improvement in Oil-Burners, of.

which the following is a specification, the principle of the invention being'herein ex plained and the best mode in which I have contemplated applying that principle, so

to distinguish it from ot er inventions.

The present inventionrelates to oil burners of the type used in heating furnaces, mufiies and the like. More particularly the invention relates to the construction of the biirner and of the mixing mechanism. The

present burner has been designed to operate oni very low air pressure and it provides means for thoroughly mixing a large body of air at low air pressure with the necessary oil vapor prion to its emission from the burner nozzle. rangement of the partsso as to beeasy of assembly and" rep'l'acement; To the" accomplishment of the foregoing and related ends,

in the side "thereof.

Other features are the ar- 'maybe adjusted.

Specification Letters Patent. Pate t d N 29 Application and October 1, 1919... Serial mqazzm.

Sion 8{pr )'vided5?with athreaded aperture 9 This extension is" threaded as at 10 for a portion of its length and is provided with a. small cap 11s0 that the device maybe packed'to be air tight.

The opening 9 in the side of the. extension s adapted to be connected to the'fuel line and this opening leads into the-hollow portion of the extension and into a fuel condult 12 which is threaded into the cap from the interior thereof. A valve stem 13 is mounted through the extension and has a threaded portion 14 engaging with screw threads 15 formed on the interior of the :extension. This valve stem extends through the fuelconduit and has at its forward end a valve portion 16 comprising a cylindri,

' cal'portion 17 having a spiral groove 18v and a cone shaped end 19, into which the spiral groove extends. At its rear end the valve stem extends through-the small cap 11 and is provided with a handle 0*'by;which' it Mounted on the forward; fuel conduit is the cone shaped ja'niixing'vjdevice said invention, then; consists" ofthe'means-{whichis-of particular interest in'the present hereinafter fully described particularly pointed. out in the claims.

The annexed drawing and-' the fellowi ng description set forth in detail certain mechanism embodying the invention,-- 'sfi ch"dis-' closed means constituting-however; but one of various mechanical forms in which the:

spective view. of the fuel valveyliig. 3vis a broken perspective view partiallyih section of the mixing device, and Fig. 4 is a broken shown in Fig. 3. i

The burner .proper consists of a T- o1nt 1 having a flange son a leg of the T which is "45 adapted to be bolted or otherwise secured to an air supply-pipe and also to support, the burner. The "ends of the, T- o1nt are threaded and on the forward endis mounted soap 4 havingia suitable," centrally located a erture 5. This cap is, oftcourse, adjust? a le longitudinally of the burner and:

On the rear end 7 of the T-joint second cap 6 is threaded which has a hollow extenconnection; This mixer-has a central ,;-Tportion 21 interiorlyI threadedfias at 22'-"and adapted to be carried ontheithreaded forwardvendfof the fuel conduit. This'jcentral portion is provided with a small centrally located aperture 23"with flared sides at its i inner end, openinggto. the fuel conduit; form- "inga; valve seat 2t'for-the valve heretofore mentioned. Around this central portion are 'mountedtwo, concentrically arranged cone shaped slee es, th'e' inner sleeve 25 being attac hed, sto*-t' e central portion by means of spiral blades 26 which are curved in the opposite, directign to the spiral groove'i'n the a valve. This innersleeve 25. extends forwardly of-o'the outlet the central portion forming a iiiix*inggchamber 28. The

second cone shapedfs'leeve 29Iis spaced from the first and-between the two arei'other spiral blades 30 turned oppositely-to the blades 26 between the; first sleeve 'and the centra L.,por-'-" tion. This sleeve 29 extends"bey6nd the first sleeve 25 forming an additional mixing-chamber 81. This outer sleeve is of less diameterj at its; forward end than the aperture in the cap, thus leaving anangular flopenin'g 32"]oetween the same',-the sleeve be- "ing adapted to be approximately in line with the inner'surfaceof the cap.

I the outer sleeve and the T-joint. The oil is supplied past the valve by which it is given a spiral motion so that it flows out of the aperture in the form of'vapor or spray with a whirling motion from left to right. At

'this point it is mixed with a blast of air which flows between the central portion and the inner sleeve and which blast is given a whirling motion in the opposite (llI'GGlJlOIl' to the oil vapor or fromright to left. The air and the oil vapor is thus mixed in the first chamber 28 and then flows outwardly where it meets with the second air blast from between the two sleeves and which is whirling from left to right and is thus more thoroughly mixed in the second mixing chamber 31. The mixture then flows out from the second mixing chamber 31. to the aperture in the cap where it meets with the third air blast coming in around the outer sleeve 29 before it passes out of the opening in the.cap which acts as the burner nozzle.. I

'Heretofore oil burners have usually been operated by means of an air blast under considerable pressure, the air and the. oil being sprayed out of the nozzle and into the furnace where they are burned. In the present device the air capacity is large and the air is supplied at a very low pressure,

approximately16'to 18 oz. being sufiicient,.

while the oil is supplied under pressure of about 15 lbs. By means of the large air openings it has been found possible in a 2 inch burner to use approximately 25 cubic feet of air per minute per gallon offuel per hour.

Marked advantages areobtained"by using the air under low pressure and supplying it in a large volume so that it 'is'thoroughly' mixed with a fuel vapor before being-11 livered to the furnaoe. The actualmiz'zin'g' occupies-three steps, the air being blowninto the fuel vaporthrough three angular openings, the blades within the emng giving the air a whirling action, first in one direction and then in another sothat'colfi plete mixing and vaporization is obtained before the mixture is burned.v

The construction of the burner 7 is such that the entire mixing device maybe readily removed without disturbing the burner itself. -By disconnecting the fuel line-the'entire mixer may be removed by unscrewing the rear cap 6 as the fuel conduit and mixer are carried by this cap. The valve and valve stem are also carried by the capand may be removed by unscrewing the small cap on the extension. The parts may thus be readily cleaned and replaced or new parts inserted as required, quickly and readily no special tools being required. The cost of manufacture, assembly and repair is thus reduced and a very simple and satisfactory burner produced.

The adjustment and control of the burner The operation and adjustment is simple and does not require a skilled operator, and it has been found that the burner does not smoke, smell or drop oil at any time during its operation. With this burner it has been found easily possible to maintain from 2500 to 3000 of heat upon the fuel consumption mentioned above.

Other modes of app-lying the principle of my invention may be employed instead of the one explained, change, being made as regards the mechanism herein disclosed, provided the means stated by any following claims or the equivalent or such stated means be employed.

I therefore particularly point out and distinctlg claim as my invention:

1. 11 an oil burner, the combination of T- joint casing, having an air inlet, a cap removably attached tosaid T-joint, a fuel conduit removably attached to said cap and ex-' tending forwardly of said 'T-joint,.and a mixing member removably attached to said conduit and consisting of aseries of cone shaped sleeves, spaced from each other and attached to each other by *sp iralblades, the blades between successive sleeves spiraling in opposite directions. A

I 2. In an oil burner, the combination of T-j oint burner casing having threaded ends, and an air} inlet and aper'ture cap adjustably mounted on the forward end, a cap removably mounted on the rear end, a fuel conduit removably attached to said rear cap, extending forwardly of said casing, and a cone. shaped mixing device removably attached to said conduit and comprising a central portion having afuel outlet, a cone shaped sleeve spaced fromsaid central portion and extending therebeyond, spiral blades between said central portion and said sleeve, a

se'cOnd slee've spaced from said first sleeve ably mounted on the rear end, a fuel conduit.

removably attached to said rear cap and extending forwardly of said casing, anda, cone shaped mixing device removably attached to said conduit and comprismg a central portion having a fuel outlet, a cone shaped I sleeve spaced from said central portion,

spiral blades between said central portion and said sleeve, a second sleeve spaced from said first sleeve and spiral blades between said two sleeves, said last named blades being curved oppositely to said first named blades, said inner sleeve extending beyond said central portion and thus forming a mixing chamber, said second sleeve extending beyond said first sleeve and forming a second mixing chamber. p

4. A mixing device for oil burners consisting of a cylindrical casing having an outlet vopening, and a mixer mounted adjacent such opening, said mixer comprising a central portion having a fuel outlet adapted to spray such fuel in a spiral direction, a sleeve surrounding such central portion and spaced therefrom, said sleeve extending in front of said central portion to form a mixing chamber, spiral blades between said sleeve andsaid central portion to give a whirling action to the air in the opposite direction to the whirling of the fuel, a second sleeve spaced from said first sleeve and extending in front thereof to form a second mixing chamber, spiral blades between said two sleeves to give a whirling action to the air in the same direction as the whirling action of the fuel, said second sleeve extending to approximately the outlet opening but being smaller to leave an annular opening as an additional air inlet.

5. A mixing device for oil burners consisting of a cylindrical casing having an adjustable cap provided with an outlet opening, and a mixer mounted adjacent such opening, said mixer comprising a central the whirling of such fuel, a second sleeve spaced from said first sleeve and extending in front thereof to form a second mixing chamber, spiral blades between said two sleeves to give a whirling action to the air in the same direction as the whirling action of the fuel, said second sleeve being of less diameter than such outlet opening to leave an annular opening for additional air, said cap being adjustable to vary such annular opening.

Signed by me, this 26th day of September, 1919. t

BERTRAM s. ROTHWELL. 

